In printworks, particularly in the newspaper field, the printing products obtained from the rotary press are frequently converted into the form of tabloids, i.e. single or multiply folded printed sheets and are in this way supplied to further processing stages. The equipment set up for such operations are therefore specially adapted to the processing formats. In newspaper production this means that relatively large format tabloids with dimensions of e.g. 30.times.50 cm are located in the means following the press. Subsequently such tabloids are further processed into double or treble-folds.
Of late there has been an increasing need for using the rotary press and the means following it for a broader spectrum of printworks products. This is inter alia due to the fact that modern rotary presses, apart from multi-colour printing, permit high quality offset printing and can therefore be increasingly used for brochures, magazines and other products. It is simultaneously possible within the offset printing process to quickly produce printing plates and therefore ensure that the printing products are very up-to-date. In view of the relatively high costs for the press and conveying systems, there is a need for a maximum utilization of the system, i.e. in the field of newspaper production this should occur on a daily basis. However, possibilities are limited by the means following the press, because they cannot be used for the further processing of the tabloids conventionally occurring with offset printing or possibly double-folds to relatively small size brochures and the like. A further problem is that an additional fold on the tabloid or on the double fold leads to unattractive creases on the bundle, which cannot be eliminated even following the final processing or the cutting up of a fold. This disadvantage generally leads to unacceptable deformations on folding a tabloid. Such quality losses are highly undesired. In addition, the final processing of the tabloids to a small or medium format magazine end product additionally requires in part relatively slow working steps, so that conveying and processing plants existing with conventional methods must have a complicated construction so as not to become overtaxed regarding the processing capacity e.g. in a timed operation.
If the tabloid processing speed is to reach 40000 to 50000 copies per hour, in the case of conventional plants fundamental problems occur. Attempts have been made to cope with such speeds in high capacity plants. However, this leads to a rapid increase in plant costs and in part physical processing limits are encountered.